Myocardial infarction: early discharge was not clearly less effective than traditional discharge.

Clinical bottom line (level 1b-)

  1. Low risk patients with acute myocardial infarction who were given accelerated treatment and discharged early had no clear difference in death, reinfarction, unstable ischaemia, stroke or congestive heart failure, than those given traditional treatment.
Grines et al: Journal of the American College of Cardiology 1998; 31 (5): 967-972
Expires March 2003

The study

Unblinded ?concealed randomised trial ?with intention-to-treat
Setting: 34 clinical centres in 5 countries

471 patients (aged mean 56 years, 76% male) Symptom onset <12 hours duration and evidence of myocardial infarction on ECG, presence of left bundle branch block or non diagnostic ECG, angiographic evidence of MI that was determined by the presence of an occluded vessel and regional ventricular dysfunction.

Excluded if
  • cardiogenic shock or clinical indications for intraaortic balloon pumping in the emergency room
  • lack of peripheral vascular access
  • bleeding risk prohibiting the use of aspirin and heparin

Note:

  • Patients were stratified into low and high risk groups. Low risk status required that all of the following criteria be met: age = 70 years, no persistent arrhythmias after reperfusion (requiring lidocaine infusion or pacemaker), one- or two-vessel disease ( = 70% stenosis). Left ventricular ejection fraction >45% and successful percutaneous transluminal coronary angioplasty. Low risk patients were randomised to accelerated or traditional treatments.


Control Group: (n = 234, 234 analysed): Traditional care- admission to a coronary care unit, noninvasive testing that was routine for the enrolling institution, intravenous heparin for 72 hours and a hospital stay of at least 5 days.
Experimental Group: (n = 237, 237 analysed): Accelerated care- admission to a non intensive care unit that was typically used for patients who would have elective percutaneous transluminal coronary angioplasty, and full dose heparin for 48 hours, followed by half dose heparin for an additional 12 hours to avoid a rebound hypercoagulable state. Noninvasive testing was not recommended, and the patients were to be discharged on day 3 in the absence of clinical contraindications such as arrhythmia, hypotension, chest pain, congestive heart failure, stroke, renal insufficiency, sepsis or other conditions requiring in-hospital treatment.
All patients were given chewable aspirin (325 mg), a 10,000 U bolus of heparin, intravenous nitroglycerin and, in the absence of contraindications, intravenous beta-adrenergic blocking agents.
96% followed for 6 months

The evidence

Outcome Time to outcome CEREERRRR
(95% CI)		ARR
(95% CI)		NNT
(95% CI)
death 6 months 1
(0.4%)		 2
(0.8%)		 -97%
(-2063% to 82%)		 -0.42%
(-1.9% to 1.0%)		 -240
(NNT = 54 to infinity;
NNH = 98 to infinity)
reinfarction 6 months 1
(0.4%)		 2
(0.8%)		 -97%
(-2063% to 82%)		 -0.42%
(-1.9% to 1.0%)		 -240
(NNT = 54 to infinity;
NNH = 98 to infinity)
unstable ischaemia 6 months 28
(12.0%)		 24
(10.1%)		 15.0%
(-42.0% to 49.0%)		 1.84%
(-3.82% to 7.50%)		 54
(NNT = 13 to infinity;
NNH = 26 to infinity)
stroke 6 months 6
(2.56%)		 1
(0.42%)		 84.0%
(-36.0% to 98.0%)		 2.14%
(-0.04% to 4.33%)		 47
(NNT = 23 to infinity;
NNH = 2234 to infinity)
congestive heart failure 6 months 10
(4.27%)		 11
(4.64%)		 -9.00%
(-151% to 53%)		 -0.37%
(-4.09% to 3.36%)		 -272
(NNT = 30 to infinity;
NNH = 24 to infinity)
  • 95 (41%) patients in the accelerated care group stayed in hospital >3 days. 57 of these were for pre-defined criteria, the other 38 were through 'reluctance to discharge'.

Citation

  1. Grines CL, Marsalese DL, Brodie B, et al: Safety and cost-effectiveness of early discharge after primary angioplasty in low risk patients with acute myocardial infarction. Journal of the American College of Cardiology 1998; 31 (5): 967-972
Contributor: Clare Wotton and Bob Phillips, January 2000
Reviewer:

Clinical Question.
Patient acute myocardial infarction at low risk
Intervention or Exposure early discharge after primary angioplasty
Comparison no early discharge
Outcome death and reinfarction